Century Plaza Low-Calorie Buttermilk Dressing

The Century Plaza Hotel is an upscale hotel located in the Century City area of Los Angeles. Their chef has concocted this dressing recipe for patrons who want a creamy salad dressing that is not too high in calories. The hotel claims it's about 10 calories per tablespoon.
The recipe was published several years ago in the reader request column of the Los Angeles Times.